Field of the Invention
The present invention relates to techniques for using a relay apparatus to grant access authority to a communication apparatus with an authorization server.
Description of the Related Art
Recently, there are cellular phones, digital cameras, and the like that have functions for accessing resource servers for content sharing services, communication services, and the like on the Internet. A user can upload image content s/he captured to a photo sharing service, send messages to friends, or the like by using such communication apparatuses. Normally, a resource server for a photo sharing service or the like manages access authority for resources such as content, files, and the like on the resource server in tandem with an authorization server (Japanese Patent Laid-Open No. 2011-39793).
Authorization servers are increasingly using the OAuth protocol to manage (grant) access authority. According to OAuth, first, a communication apparatus obtains, from an authorization server, an access token indicating access authority for a desired resource and a refresh token for refreshing the access token. Then, when making a request to obtain the desired resource from a resource server, the communication apparatus issues the request along with the access token obtained from the authorization server. The resource server sends the requested resource to the communication apparatus only in the case where the access token is valid. In the case where the access token has expired, the communication apparatus can refresh the access token by providing the refresh token to the authorization server. Meanwhile, the user's authorization is required when delegating the user's access authority to the communication apparatus using the OAuth protocol. Normally, the authorization server presents an HTML window for the user to carry out an operation for granting the access authority, and the user carries out the operation for granting the access authority in a web browser.
However, according to the conventional technique, the HTML window provided by the authorization server cannot be displayed in the case where the communication apparatus does not include a web browser due to, for example, memory size limits or the like, and thus users have been unable to grant access authority using the OAuth protocol.